Checking for Current

CHECKING FOR CURRENT

Now that the vehicle has been shut down and disabled, triple check that everything has worked properly. You can’t be too careful.

While wearing the insulating gloves, take a voltage reading. Select “volts DC” on your multimeter and ensure your meter is working correctly by testing it on the 12V battery. If the multimeter is damaged or defective it can give a false reading of zero.

A hybrid’s HV circuitry is isolated from the chassis ground, which forces us to take readings right from the HV connection. OEM service information will give you the specifics for each vehicle. [Will operators know what OEM service information is and where to find it? Is it the same as the owner’s manual?]

Hydro workers adhere to the “one-hand rule” when dealing with power lines. Only one hand can be working on the HV system. This rule exists to lower the risk of electrical shock. Even though you are wearing insulating gloves, you can never be too safe. If you were to be shocked by the system, you could be severely burned or killed.

Connect your lead equipped with the insulated alligator clip to one of the circuit’s terminals, then contact with another terminal to take a reading. Never use more than one hand doing this.

If you leave the terminals disconnected, wrap them with electrical tape, removing the possibility of arcing if the system were to power up.

Never back-probe HV connectors. This damages them beyond repair. Never use any aerosol product to clean around the circuit. This could electrically charge the air in the area, making it conductive.

Once you’ve taken a reading and ensured the system is completely powered down, you can work without insulating gloves and focus on the task at hand.